A “full cone spray nozzle” is a nozzle in which the liquid which is discharged from the nozzle is sprayed in a conical shape. “Full cone” means the droplets of the discharged liquid are filled to the center of the cone.
A full cone spray nozzle generally has a tubular nozzle body inside of which there is a vane structure which has swirl flow generating means. There are various shapes of vane structures, but the liquid which is supplied from the upstream end of the nozzle body passes the vane structure and flows to the downstream end of the nozzle body during which time the swirl flow generating means of the vane structure makes it swirl and form an eddy current.
The liquid which flows to the downstream side of the nozzle body in this way is sprayed from the downstream end of the nozzle body in a full cone shape.
PLT 1 discloses a full cone spray nozzle which has a bore at the center part of the vane structure and is provided with a swirl flow generating means comprised of a plurality of swirl paths which are formed in an inclined direction at the outer circumferential surface of the vane structure. This full cone spray nozzle aims at generating a spray pattern of a uniform flow rate distribution by a wide angle (65 to 75°) with a uniform flow rate distribution.
PLT 2 discloses a full cone spray nozzle which lacks the center bore of the vane structure and makes the vane structure as a whole an X-shape. According to this full cone spray nozzle, it is possible to generate a spray pattern which has a bell-shaped flow rate distribution which has a maximum flow rate at the center of the spray region of a narrow spray angle (about 30° or less).
PLT 3 discloses a nozzle which has channel grooves in an inclined direction at the outer circumference of the vane structure, has a downstream side of the vane structure formed into a cone shape, and ejects a hollow cone shaped spray. A “hollow cone shaped spray” is a spray which is cone shaped at its outside, but does not have droplets of the discharged liquid filled to the center of the cone. Therefore, according to this nozzle, it possible to give a swirl force to a low pressure liquid and generate a fine, stable hollow cone spray, but a full cone spray is not produced.